The problems of triboelectric charging and other forms of static charge buildup have long provided problems in various commercial areas. A large number of various methods have been developed over the years for dealing with this problem. Amongst the various techniques used to reduce electrostatic charge buildup are the application of conductive film coatings to surfaces, the inclusion of conductive particulate matter or fibers within the composition, the matching of work functions of surfaces in movable contact with each other, exterior grounding of surfaces subject to charge, and even coating with compositions that suppress spark discharge. Each of these procedures has its own advantages and disadvantages, but are generally regarded in the art as equivalent in their ability to reduce static charge buildup.
Certain problems relating to static charge buildup on rotary magnetic disk record assemblies have already been noted and solved. U.S. Pat. No. 4,354,213 discloses the use of a porous, fibrous, low-friction, antistatic liner material with a lubricant thereon between the rotating circular disk and the interior surface of the jacket. This antistatic layer reduces triboelectric charge buildup from the motion of the rotating disk against the jacket or the liner.
U.S. Pat. No. 4,038,693 discloses the use of an electrically conductive layer on the inside surface of the jacket for draining away electrostatic charge on the jacket. Materials such as high carbon black content inks are shown for use in forming the dry interior layer.